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P/N 42-9470 11/07 Copyright 2007 Mestek, Inc.
Cast iron condensing boiler
Cast iron condensing boiler
— Installation and operation manual
Fill and test the system
Failure to adhere to the following could result in
boiler section failure, resulting in potential for
severe personal injury, death or substantial property
damage.
Flush and clean the system before fi lling.
Provide clean water to fi ll the system
Water quality must be as prescribed in this manual.
Follow the system water checklist
Follow the guidelines in this section to fi ll and test the system. Th
e system wa-
ter quality must meet the conditions given, and you and the owner must make
sure the conditions will be maintained throughout the life of the boiler.
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Closed systems only
Do not apply the
200i
boiler on open systems, such as direct heating of domestic
water, swimming pool heating or process applications that use system water. For
these applications, you must install a heat exchanger.
Hard water conditions
If water hardness exceeds 7 grains, use a water soft ener in the fi ll line to soft en the
water before it enters the system.
On multiple boiler commercial installations, the large volume of water in the sys-
tem can contain substantial mineral salts, even if the fi ll water hardness is less than
7 grains. Th ese salts can deposit in the boiler heat exchanger as limestone, causing
possible section damage. Commercial installations should usually be fi lled with
soft water to avoid this problem.
Prevent oxygen corrosion
Make sure the system is provided with adequate automatic air elimination, including
an in-line air separator and automatic air vents (diaphragm or bladder tank systems)
or piping to the expansion tank (closed-type expansion tank systems).
Do not connect the
200i
boiler to a system that contains non-barrier radiant tubing.
Non-barrier tubing can allow oxygen to enter the system, causing oxygen corrosion
of the boiler heat exchanger.
Flush and clean the system
Flush the system to remove sediment, fl ux, fi lings and other foreign matt er. Use
cleaning chemicals sold for use in hydronic systems.
Replacement boiler installations oft en have large amounts of accumulated sediment
and corrosion that must be removed to ensure boiler life and reliable operation.
Flush each zone of multi-zone systems individually using the purge valves and iso-
lation valves in the system.
Flush until the water runs clean.
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Aft er fl ushing the system thoroughly, use trisodium phos-
phate or other chemical sold for cleaning hydronic systems
to remove sediment and sludge.
Use caution when working with chemicals,
following all guidelines specifi ed by the chemical
supplier and the applicable codes.
Purge air from the system
Th e system should be installed with purge valves such as
those shown in the suggested piping in this manual. Purging
is the most effi cient way to fi ll the system and remove most
of the air.
Connect a hose to a purge valve and run the hose to an ap-
propriate draining area. (When fi lling with antifreeze solution,
run the hose back to the solution tank.)
Close all isolation valves in the system.
Open the manual valve (or quick-fi ll valve) on the make-up
water line. (When fi lling the system with glycol, connect
from the glycol pump to one of the purge valves with a hose.)
Purge each zone separately by opening the isolation valves
for that zone, allowing water to push the air through and fi ll
the zone. Aft er fi lling the zone, close the isolation valves and
move to the next zone.
Fill and purge the boiler loop in the same manner.
Aft er the boiler is operated for a while, air entrained in the
fi ll water will bubble out of the water as it heats, and will
have to be removed by using air vents in the system.
Add a chemical inhibitor
Aft er purging and fi lling the system, add a chemical inhibi-
tor sold for use in hydronic systems to prevent limestone
and magnetite deposits from forming, and to protect the
boiler from galvanic corrosion.
Water pH
Th e boiler water must be slightly basic, never acidic. Use lit-
mus paper to check pH, which should range from 7.0 mini-
mum to 8.5 maximum.
If pH does not comply, provide water chemistry correction
from a qualifi ed water treatment specialist. If required, make
sure that the owner is aware and that the regimen will be
continued.
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